[Ns-developers] ns-3 and future development

[Mathieu Lacage]

On Mon, 2006-01-16 at 22:08 -0800, Tom Henderson wrote:
> > Is the following not simple enough ?
> > Simulation::insert_at_s (10.0, make_event (&MyClass::timeout, my_class, 
> > context));
> 
> Ability to schedule, reschedule, cancel, and inquire about the status of 
> the timer.  Might require the above method returning a handle to the 
> event, and some "status_" flag in the event that can be used to 
> deactivate it without having to traverse the data structure to find the 
> event-- this stuff has been worked out before in other simulators.


I did spend a bit of time thinking more about this API. Would you be
okay with something like this:

event-cancellable.h:
class EventCancellable: public Event {
public:
	EventCancellable () 
	: m_state (INITIAL) {}

	bool is_canceled (void) {
		return (m_state == CANCEL)?true:false;
	}
	void cancel (void) {
		assert (m_state == INITIAL);
		m_state = CANCEL;
	}
private
	typedef {
		INITIAL = 0,
		CANCEL  = 1,
		DEAD    = 2
	};
	virtual void notify (void) {
		assert (m_state != DEAD);
		if (!m_canceled) {
			do_notify ();
		}
		delete this;
	}
	~EventCancellable () {
		m_state = DEAD;
	}
	virtual void do_notify (void) = 0;
	uint8_t m_state : 2;
};

and event-cancellable.tcc which defines a bunch of
make_cancellable_event () functions

This API is maybe a bit too simplistic. What do you think ?

Mathieu
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